Schizophrenia
This article will be the featured article for February, 2012. Please help us improve it in the meantime. ' Schizophrenia' is a serious mental illness characterised by hallucinations, delusions, and psychosis. It is one of the mental diseases in the schizophrenia spectrum, which contains similar illnesses such as Schizoaffective disorder, Schizotypal disorder, Schizoid personality disorder, and others. People with schizophrenia have a strange or altered perception of reality. It's well known that schizophrenia is characterized by hallucinations and delusions, but also can impair thinking and attention, a breakdown in thought processes, and poor emotional response. Treatments for Schizophrenia are typically anti-psychotics, such as geodon, risperidone, and haldol. These medications prevent the symptoms of psychosis. The disease Schizophrenia usually manifests as auditory hallucinations, paranoid or bizarre delusions, and disorganized speech and thinking. It usually starts to manifest itself in young adulthood (often before the age of 19). It affects somewhere between 0.3-0.7% of people worldwide and is known in all cultures, both sexes, and all ethnic groups. Like most other mental illnesses, schizophrenia has to be dianosed using a differential diagnosis based both on observations of the patient and description of the patient's own experiences. The cause of the disease is unknown, alhtough it is clear that genetic, early environment, neurobiology, psychological processes and social processes all contribute to risk factors for the disease. Both prescription and recreational drugs can often worsen the symptoms. Current research is focussed on neurobiological causes but to date, no single organic cause for the disease has been identified. Because each patient can have unique symptoms, there is also debate about whether schizophrenia is a distinct disease or a set of related disorders. Although the etymology of the name is the Greek for "split mind", and the disease is often thought to be one of "split personalities", this does not accurately describe the disease. Most schizophrenics are now treated with anti-psychotics, which help alleviate symptoms, but often have deleterious side effects. These medications suppress dopamine and serotonin receptors. In addition, psychotherapy, vocational and social rehabilitation are used as supplementary tools. Where the risk to the patient or others is extreme, involuntary hospitalization is necessary. However, hospital stays for schizophrenics continue to get shorter and less frequent. Although the condition largely affects cognition, it also contributes to emotional and behavioral problems. Scizophrenics often have other major mental illnesses, such as clinical depression and anxiety disorders. Almost half of schizophrenics abuse drugs. Long term poverty, unemployment and homelessness are common. Their average life expectancy is 12-15 years shorter than others of the same sex and ethnicity, and their suicide rate is about 5% higher than the general population. Symptoms Schizophrenia usually presents with: *Hallucinations, usually auditory, but ocassionally visual *Delusions, usually something of a bizarre nature, or a feeling that they are being persecuted *Disorganized thinking and speech, ranging from a loss of train of thought, through sentences that are only loosely connected, and finally confused and repetitious language. *Social withdrawal leading to social isolation *Sloppiness of dress and hygiene *Loss of motivation and judgment *Emotional difficulty, including lack of responsiveness *Inability to comprehend social interactions and conventions *Paranoia *In extreme cases, inability or unwillingness to speak, remaining motionless in uncomfortable or bizarre postures, meaningless agitation and catatonia In some cases, a set of preliminary symptoms can be identified that can lead to early treatment. These include: *Transient or self-limiting psychosis *Social withdrawal *Irritability *Intense feelings of depression *Clumsiness To distinguish schizophrenia from other common psychiatric disorders, the psychiatrist Kurt Schnieder developed his "First-ranked symptoms". However, the usefulness of these symptoms in confirming a diagnosis are currently questioned, even though they appear in most authoritative texts. *Delusions of being controlled by an external force *The belief that thought are either being inserted into or withdrawn from the conscious mind *The belief that one's thoughts are being broadcast to other people *Hearing hallucinations that comment on the person's thoughts or actions, or hearing a conversation between different hallucinated voices More recently, schizophrenia is characterized by a set of positive and negative symptoms. Positive symptoms are those that exist in schizophrenics, but are not experienced by most individuals. These include delusions, disordered thoughts and speech, and hallucinations of all five senses that result from psychosis. In most cases, the hallucinations relate to the content of the delusions. These symptoms generally respond well to medication. Negative symptoms are deficits of emotional response or thought processes and generally do not respond to medication. These include blunted affect and lack of emotional response, poor use of speech, anhedonia, lack of desire to form relationships, and lack of motivation. These negative symptoms all contribute to the poor quality of life experienced by most patients. Causes No exact cause of the disease is known, but it is believed that genetic and environmental factors both play a role. People with a family history of schizophrenia are more likely to be diagnosed with it. However, the variability of environmental factors makes it difficult to determine just how likely any given person with a family history will be to develop the disease. A person with a parent, child or sibling with the disease has a 6.5% chance of having it. A person who has an indentical twin with the disease stands about a 40% chance of developing it. However, no specific gene has been identified as being associated with the disease, although the suspect group of genes overlaps those that play a role in bipolar disorder. Genetic science is also at a loss as to why such a disease would have developed given the workings of evolution as the disease is always maladaptive. Some environmental factors have been identified as making schizophrenia more likely, including drug use, living environment and pre-natal stress. However, there appears to be no link between parenting style and schizophrenia, although when the disease develops people in more supportive relationships tend to fare better. Living in an urban environment, even only as an adult, appears to roughly double the risk even after all other social factors have been accounted for. Social isolation, immigration, social adversity, racial discrimination, family dysfunction, unemployment and poor housing conditions also appear to play a role. Childhood abuse and trauma also appear to make schizophrenia more likely. Marijuana, cocaine and amphetamines have all been linked to increased risk, and about half of schizophrenics abuse drugs or alcohol. However, of these only marijuana has been shown to have any causal link, and the others could be an attempt to self-medicate to cope with depression, anxiety, boredom and loneliness. However, even the link with marijuana appears largely dose dependent and it's exact effect remains controversial. In addition, mere abuse of cocaine, amphetamines and alcohol can lead to psychosis which mimics schizophrenia. It should be noted that schizophrenics are also more likely to use nicotine than the general population. The pre-natal stressors that have been linked are hypoxia, infection and malnutrition. For some reason, a disproportionate number of schizophrenics are born in the first half of the year during winter and spring. Mechanism Like it's causes, the mechanism that causes the mental status changes in schizophrenia patients is also poorly understood. The best accepted model is the dopamine hypothesis, which puts the symptoms down to the brain's misinterpretation of misfiring dopamine-accepting neurons. Another hypothesis is that the disease is the result both of poor neurodevelopment and later neurodegeneration. However, this latter theory does not explain many of the symptoms that are known to occur in schizophrenics. The dopamine hypothesis was formed after it was noted that when patients were given dopamine inhibitors, their psychotic symptoms improved. In addition, amphetamines, which increase dopamines, make schizophrenic symptoms worse. In the 1990s, the improvement of PET scans confirmed this. However, this model is now believed to be incomplete as newer medication for schizophrenics appears to be just as effective despite the fact that it has less affect on dopamine and has a greater effect suppressing serotonin. It is also now believed that glutamate plays a role in the disease as autopsies of schizophrenic brains show very low levels of glutamate receptors. This hypothesis appears to be bolstered by the fact that drugs that block glutamates, like ketamine, often bring about schizophrenic like symptoms. In addition, low glutamate levels in normal adults are known to have an affect on the frontal lobe and hippocampus. However, many of these results are in question as most schizophrenics who have been autopsied were being treated with medication for most of their life. This, in and of itself, could have caused the brain changes that were observed. In addition, PET scans of schizophrenics who have not been given drug treatment appear to have identical dopamine receptors to normal control brains. Moreover, in cases where schizophrenics are noted to have lower dopamine receptor levels, it may still not be clinically significant. Studies of living brains have found notable differences in the frontal lobe, hippocampus and temporal lobes. Those who believe the condition is a neurodevelopmental disorder believe these parts of the brain do not fully develop in schizophrenics, explaining why symptoms arise in young adulthood when brain development is largely complete in most individuals. However, schizophrenics show a wide range of brain development issues and there is no one feature that distinguishes schizophrenics. Moreover, these abnormalities are common in other psychiatric disorders. However, in cases of early onset schizophrenia, there is an associated loss of grey matter in the brain which does indicate a neurodegenerative cause. MRI studies also show that schizophrenics tend to have a smaller hippocampus and a smaller ventrical than normal controls. However, these volumetric differences appear at the range of MRI detection, so it is uncertain whether these parts of the brain don't develop fully or degenerate more quickly than those of average persons. However, MRIs also find abnormalities in the prefrontal cortex, temporal cortex and anterior cingulate cortex of schizophrenics even before symptoms occur. An fMRI shows that the positive symptoms of the disease appear to originate in the medial prefrontal cortex, amygdala and hippocampus. Negative symptoms appear to originate in the ventrolateral prefrontal cortex and venial striatum. fMRIs also show that many of the cognitive difficulties experienced by schizophrenics develop in the very early steps of sensory processing. PET scans show a lack of blood flow to the left parahippocampal region and a reduced ability to metabolize glucose in the thalamus and frontal cortex. However, there is increased blood flow where thought disorders originate in the frontal and temporal regions of the brain, while decreased blood flow is characteristic of hallucinations and delusions arising from the cingulate, left frontal and temporal regions. When patients were scanned during active auditory hallucinations, there was increased blood flow in the thalami, left hippocampus, right striatum, parahippocampus, orbitofrontal and cingulate areas. CT scans show enlarged ventricles typical of decreased brain volumes. There are also notable irregularities on an EEG. Diagnosis The criteria for diagnosing schizophrenia are found in both the DSM-IV-TR and the ICD-10. A diagnosis is based on self-reported experiences of the patient, reports by others of the patient's behavior, and a full clinical work-up. Because most of the symptoms of schizophrenia are common (but very transient) in most of the population, the symptoms must meet a level of severity that in the subjective judgment of the physician is indicative of the disease and not another condition. A differential diagnosis must consider other mental illnesses bipolar disorder, borderline personality disorder, drug intoxication, drug-induced psychosis, delusional disorder, social anxiety disorder, avoidant personality disorder, and schizotypal personality disorder. It must also rule out organic disorders such as metabolic disturbance, systemic infection, syphillis, HIV, epilepsy and brain lesions. One difficulty posed by a diagnosis is that although Obsessive-Compulsive Disorder can be distinguished from schizophrenia, many patients have both conditions. The patient must show at least two of these symptoms for most of the time during a one month period: *Delusions *Hallucinations *Disorganized speech that severely impairs the ability to communicate with others *Grossly disorganized behavior (such as dressing inappropriately or crying frequently), or catatonia *Blunted affect, decline in or lack of speech, decline in or lack of motivation In the alternative, the patient must suffer from just one of these very severe symptoms: *Bizarre delusions *Auditory hallucinations that form a running commentary on the patient's actions *Hearing two or more voices In addition, the patient must also meet these two criteria *Social or occupational dysfunction, such as ability to work, personal relationships or self-care. *Signs that these disturbances have lasted at least six months. If all these criteria are not met, alternative diagnoses can be schizophreniform disorder or brief psychotic disorder. Schizophrenia is also excluded if the patient has mood disorders or pervasive developmental disorder. Subtypes Once diagnosed, the patient is usually classified into one of five subtypes of schizophrenia *Paranoid type, characterized by delusions and auditory hallucinations in the absence of thought disorders, disorganized behavior and flat affect. Delusions are generally either persecutory or grandiose and may include jealousy or extreme religious belief. *Disorganized type, characterized by the presence of both thought disorders and flat affect *Catatonic type, where the patient is immobile or only engages in agitated but purposeless movement. *Undifferentiated type, where the patient shows psychosis, but not paranoia, disorganization, or catatonia *Residual type, where the positive symptoms are of low intensity Prevention and Management Although it is hoped that early intervention will avoid the worst symptoms of schizophrenia, there is currently no conclusive proof that early treatment has any effect on the course of the disease. It is accepted that early intervention can help in the short term, particularly with psychosis, but over a period of five years, no difference can be seen. As such, treatment for the condition before symptoms appear (based on precursor symptoms) is not recommended. It is believed that persons at risk should avoid marijuana and other cannabis products. It is hoped that once the disease is better understood, intervention can be targetted at those with genetic and environmental risk factors. It is also hoped that, in future, schizophrenia can be treated as a public health issue and persons at risk because of socioeconomic factors could be screened more frequently. However, at present, there is no guarantee that resources used in such an effort might not be better used elsewhere. Schizophrenia is difficult to manage as no one treatment will work for all patients. At present, medication is the preferred approach. There is no cure for the disease so all treatment focusses on management of symptoms and improving brain function. Anti-psychotics have been the preferred approach since they were first developed in the 1950s. However, these drugs have severe side effects such as sedation, repetitive and uncontrollable body movements, neuroleptic malignant syndrome, obesity and diabetes mellitus. However, the range of anti-psychotics currently available often have more manageable side effects and older drugs used to treat schizophrenia are used less often. These drugs usually take 7-14 days to have their full effect on the patient. However, some patients fail to respond to even a combination of anti-psychotics given for a period of over six weeks. For thse patients, clozapine is used despite it's severe side effects that can include myocarditis and lowering the white blood cell count. In addition, the effectiveness of these drugs in preventing psychotic episodes is under review as many schizophrenics who use the drugs still have such episodes while schizophrenics who avoid the drugs are actually less likely to have such episodes. Severe schizophrenics usually require hospitalization, although hospital stays are getting shorter and less frequent as treatment methods improve. Many hospitals have drop-in clinics to treat schizophrenics on an out-patient basis. Behavioral therapies are also used with schizophrenics, again with mixed success. Psychotherapy has been effective, but is rarely used due to it's cost and the lack of proper training. Cognitive behavioral therapy has also been effective. However, one of the most effective forms of therapy is whole family therapy, including the patient's parents, siblings and partners in the process. Schizophrenia at Wikipedia Schizophrenia risk factors Category:Psychiatry false